Manufacture of salt by multiple-effect evaporation.



s. M. LILLIE. MANUFACTURE OF SALT BY MULTIPLE EFFECT EVAPORATION.

APPLIOATION FILED MAR.15, 1910.

atented Feb. 10, 1914.

Siea in End Wiper-End Sieam End. 2

Steam End Kaporfi'nl Steam End.

WITNESSES; INVENTORI SAMUEL MORRIS LILLIE, OF PHILADELPHIA,PENNSYLVANIA.

MANUFACTURE OF SALT Bi MULTIPLE-EFFECT EVAPORATION.

. Specification of Letters Patent.

Patented Feb. 10, 1914.

Application filed March 15, 1910. Serial No. 549,541.

brine, my vapor or heat reversing multipleeffect which is described inUnited States Letters Patent #777,114, issued December 13th, 1904, andwhich is shown in various modified constructions in my United StatesPatents #789,159, May 9th, 1905, #939,143, November 2nd, 1909, #984,376,February 8th, 1910. The construction of this multiple effect is suchthat it may be operated with either end effect of the series as thehottest effect and either end effect the coolest effect.

When one end effect is the hottest one, the other end effect is thecoolest one of the series, and vice versa. The object of this adaptationis to take advantage of the changes in temperature caused in the variouseffects of the multiple effect by the reversing of the dire tion of thevapors to prevent the formation of incrustations upon the evaporatingsurfaces during the evaporation of the brine.

My invention consists in combining with effects of the vapor reversingmultiple effect,

separating devices by which the salt crystals formed in the severaleffects by the evaporation of the brine may be separated from the brineand delivered away from the multiple effect.

An arrangement of apparatus embodying my invention is illustrated in theaccompanying drawings of which Figure 1 is an elevation, Fig. 2 is aplan view. Fig. 3 is a cross section of each of the cooks mentioned.

Referring to the figures in which like arts are indicated by likeletters or numrs, A, B and C are the three evaporator effects of aLillie vapor reversing multiple effect, each of which is constructed ina general wa as indicated in my Letters Patent referre to in thepreceding and also in earlier Letters Patent granted to me, that is,each effect is horizontal, is divided into two chambers by a verticalpartition, which also serves as a tube plate, near one end of theeffect. This partition or tube plate is indicated in the plan Fig. 2 bythe dotted lines ate in the .case of each effect. The

smaller of these chambers is designated the steam end and the larger thevapor end. Horizontal evaporating tubes located in the vapor end openthrough this tube plate into thesteam end. The ends of the tubes in thevapor end are closed save for a small air vent and extend only part waythrough the vapor end chamber. The heat ing agent steam or vapor is ledinto the steam end chamber, whence it flows into the evaporating tubesand causes evaporation from the liquid in contact with the tubes in thevapor end chamber, which is provided with a vapor escape main. In theelevation, Fig. 1, the effect B is shown in vertical section takenacross the broken line X-X Fig. 2. The section discloses to view theclosed ends of the evaporating tubes in effect B and a perforateddistributing plate above the tubes. The effects are turned end for endso that the steam end of each effect is in line with the vapor end ofeach adjacent effect. In the drawings the respective ends of each effectare indicated by the designations Steam end and Vapor end. The vapor endof each effect is connected with the steam end of each adjacent effectby a vapor main fitted with a valve. The middle ef-' fect B is connectedwith the steam end of effect A by a vapor main 1 fitted with a valve 8and it is connected with the steam end of the effect C by a vapor main 7equipped with the valve 9. The vapor end of effect A is connected withthe steam end of effect B by the main 5 fitted with the valve 10 and thevapor end of effect C is connected with the steam end of effect B by thevapor main 6 fitted with the valve 11. The vapor end of the effect Aconnects by the vapor main 12 with the condenser 13, having the leg pipeL, and the vapor end of the effect U connects by the vapor main 14 withthe condenser 15, having the leg. pipe L. The condensers 13 and 15 areejector condensers in which the cool ig water serves to maintain thevacuum as :11 as to condense the vapors. Condenser 13 is supplied withwater'through the pipe 16 fitted with a valve 17 and condenser 15 issupplied with water through pipe 18 fitted with a valve 19. Although notshown, a steam supply pipe fitted with valve leads 7 into the steam endof efiect A at N, and a similar steam pipe leads into the steam end ofeffect 0 at Nsee Fig. 2.

On the under side of each eflect is a well which opens below into.acentrifugal circulating pump 1.- The three pumps are shown on a commonshaft 2, which is revolved'by a motor M or byother suitable means.Between the eiiects A and B is the settler S.-

Between the effects B and C is the settler S both of the sameconstruction. Each settler is 'an inverted four-sided pyramid with sidesparallel and perpendicular to the length of the triple effect. In Fig. 2the top plate or cover of settler S is removed. In Fig. 1 interiorconstruction of the settler S is indicated by dotted lines which show anarrow passage O and O inside the settler and on opposite sides of thesame. These passages O and O are closed below and open above near thetop of the settler. The passage 0 has an inlet nozzle with whichconnects the pipe The pas-- sage O has a discharge nozzle with whichconnects the pipe 36. The settler S has inside passages similar to OO,of settler S,

and with them connect pipes 25 and 40.

' S is a settler opeh at the top, and ot' the general shape of aninverted truncated foursidcd pyramid. On one side or face of thissettler and covering the upper portion of it is the thin inlet passage Owhich opens above into the settler near the top and intowhich belowopens the inlet pipe 27. The

- settler S serves as a boot for the bucket elevator E. In front of thiselevator in the settler S is the partition 0' which forms in the settlerin front ofthe elevator a buffer like compartn'ient. Afpipe 2Ocommunicates with a discharge nozzle can each of the three circulatingpumps 1 by a connection 21. Through the three way cock 22 itcommunicates with the pipe23 leading into settler i" at the side, whichpipe 23,. may, by the said cock and .pipe QO, be connected with the pump1 o'f-eitherB or C. Pipe 20 also communicates through the three way cock24 with the pipe 25 which leadsinto settler S at. the side, which pipe25 can be connected tothe pump 1 of either eiiect A or B through thecock 24 and pipe 20. The pipe 27 leading into the passage 0 on settler Sconnects through the three-way cock 26 either with the pipe 20 or withthe pipe 28. Connecting also with a. discharge nozzle from each of thecentrifugal pumps 1 is a pipe 29, which connects through the three S ashort way above its lower end or apex. Pipe 34 is a drain pipe withvalve connections 35 to a discharge from each circulating pump. From theside of the settler S opposite to the pipe 23 a pipe 36 leads upto thethree way cook 37 through which it communicates either with the pipe 38delivering upon the distributing plate in the body 0 or with thepipe 39?which delivers upon the distributing plate in body B. From the side ofthe settler S opposite to the pipe 25 a pipe 40 leads to the three waycook 41 by which it can communicate either wit-h the pipe 39 deliveringupon the distributing plate in the eifect B or with thepipe 42 whichdelivers upon the distributing plate inv effect A. From inside thesettler S back of partition 29 a pipe 43 leads to the three way cock 44through which it may communicate either with the pipe 42 which deliversupon the distributingplate in the effect A, or with the pipe 45 whichconnects with the p1pe 38, and through it delivers upon the distributingplate in the effect C. Pipe 43 is fitted with the balanced valve V whichis operated by the connected float F. The settler S at its bottom orapex. is connected to the three Way cook 39, through which it maycommunicate through the connecting pipe 40 with the Well W of effect B,or through the connecting pipe 41 with the well W of effect A. Thesettler S connects at its bottom or apex with the three way cock 46through which it may communicate, by the connecting pipe 43 with thewell 7 of effect B, or by the connecting pipe 44 with the well of thecfi'ect C. The valved pipe f leading into the well lV' of effect Aisthefresh brine feed to that eii'cct, the valved pipe f is a fresh brinefeed to effect- 0 and .the valved pipe F is a -fresh brine feed into theopen settler S By Fig, 3 is indicated the construction of any oneof thethree way cocks herein mentioned.

The operation of the described combina-j tion of parts is as follows,viz: First, let it be assumed that the apparatus is charged with brineand is operating with A the hot test-effect and C the coolest efi'ect.Steam is 5 entering the steam end of A at N, and steam to C at N is shutoff. \Vater is passing through the pipe 18 into the condenser 15 ofeffect 0 and water is shut off from condenser 13 of effect A. The vaporvalves 12 10 and 9 are open, the vapor valves 8 and 1-1 are closed, andthe course of the heat or vapors through the series is as indicated bythe single barbed arrowssee Fig, 2. The

one of which is indicated in Fig. l at 1 on effect B. The settlers S. i"are full of brine and the settler is also full of brine to effects areeach charged with brine up to the desired polnts asmdicaled by gageglasses,

about the'height indicated in Fig. 1. The 139 [tals which are formed inthe brine in A by ,through the pipe 43, etc., is automatically regulatedby the balanced valve V and its its circulating pump 1, and pipes 20 and25 intoitheside of the settler S, across near .29, cock 32 and pipe 33into the settler S a little above its apex and passes back into lowerpart of settler S. back into the effect 1,oae,e57. 8 I

elevator E and the circulating pumps 1 are running and the fresh brineis feeding into effect A through the feed pipe f as controlledby thehand valve in the latter. The three way co'cks are set so that movementsof the brine are as follows: The brine is circulating from the bottom ofeffect A through the top .of the settler, down on the other side and bythe pipes 40 and 42 through the top of effect A upon its perforateddistributing plate by which the brine is distributed over thebattery ofevaporating tubes below, as indicated at effect B, Fig. l. i The saltcrygy its evaporation, pass with the circulating brine into the settlerS, and settle away from the brine as it flows across near the top of thesettler and falls down toward and to the bottom or apex of the settlerdue to the salt crystals having a greater specific gravity than thebrine. Brine is circulating from effect B through the pipes 20 and 23into the side of settler S up and across the same A portion of brinefrom effect B is forced by its circulating pump 1 through the pipe thewell W of effect B through the cock 39 and p'pe 40 This brine whichcirculates from he bottom of effect B through the B carries with it intothe effect B the salt which comes into the settler S, from effect" A.The brine which circulates, as above descrihed, from the bottom ofeffect B through the settler S, carries with it and deposits in thesettler S, this salt which comes for ward from the settler S into B, andalso the salt crystals which are formed by the evaporation of brine inB. Hence the salt crystals formed by evaporation in effects A and B aredeposited in settler S. Brine is circulating from the bottom of effect Cthrough its circulating pump l through the pipe 28, cock 26 and pipe 27into the passage 0 on the side of settler S thence across, the top ofthe brine in the settler over the partition 72 and back through the pipe43, rock 44, and pipes 4-5 and 38 into effect C tlifough the top. Theflow hack floa't F to compensate for the flow of brine into the settlerfrom the effect (l through the pipes 28 and 27 and so maintain'the levelofth brine in S constant within certain limits.- A' portion of brinecirculates from effect 0 through the pipe 29. cock 30 and pipe al,intothe settler S a little above its bottomorfeapex and. through thecock 46 at toward A, the coolest effect.

its apex and pipe 44 back into the effect G through its well W. Thiscirculation of brine from the effect C through the settler 5' back intothe effect C, brings into the lat-- ter the salt crystals which depositin the settler, that is the salt crystals formed by evaporation ineffects A and B. These salt crystals together with those formed byevaporation in effect (J, that is the crystals formed by evaporation inall three effects, are carried by the brine circulating from the effeetC through the open settler S into the latter, in which they fall fromthe brine as it flows across the surface of the brine in the settler andsettle to the bottom and are taken away by the bucket elevator E.

The regulation of the brine levels in the effects A, B, and C is done asfollowsi The hand valve in the brine feed pipe to the effect A, thehottest effect, is regulated to maintain the desired level of brine ineffect A. The three way cocks and 39 are regulated so that the flow fromthe bottom of settler S through pipe 40 into the effect B is in excessof the flow from effect B through pipes 29 and 33 into the settler Sthis excess 'is' really a feed or flow of brine from the effect Athrough the settler b into effect B. This feed can be regulated inamount by either the cock or the cock 39, the other cock being set onlypart way open, to maintain the desired level of brine in effect B,

and is so done. The three way cocks 30 and i I I 46 are regulated sothat the flow of brine from the bottom of settler S into the effect Othrough the pipe 44 is in excess of the flow from the effect 0 throughthe pipes 29 and 31 into the settler. This excess is a feed of brinefrom the effect B through the settler S into the effect 0: this feed isregulated in amount to maintain the desired level of brine in effect C,either by the cock 30 or by the cook 46, the other cock being set onlypart way open. It may be noted here that their levers are so set up onthe cooks that they all point or incline toward the coolest effect andit will be observed from what follows that if the levers of all thecocks be turned to t opposite side of the nearest vertical radius, thecocks will all be set for working with O the hottest effect and A thecoolest effect and will all point or incline The apparatus may bechanged from operating as above, viz. with A the hottest effect and Cthe coolest effect, to operating with O the hottest effect and A thecoolest as follows: Shut off steam'from effect Aiat N, close valve inbrine fee'd pipe f to effect.A, and close cocks 30, 32, 39 and 46 byturning their levers into the nearest vertical position. All flow orfeed of brine is now stopped into A and from A to B and from B to C, butthe circulation of brine is still in force through each effect and itsconnected settler. Preferably after the pressure (or vacuums) in thethree effects are nearly equalized, shut water 05 the condenser by thevalve 19 in the Water line 18,.and turn water into the condenser 13 byopening the valve 17 in the water line 16. Close now the cocks 22, 24and 26 by moving their levers into the nearest vertical position. Turnthe inclined levers of the cocks 41 and 37 and 44 to the inclination onthe other side of the nearest vertical position and then further movethe. levers of the cocks 22, 24 and 26 to incline to the vertical fromthe sides opposite to what they were when working with A the hottestefi'ect.

Open the valve 8 .in vapor main 4 and valve 11 in vapor main 6, andclose the valves 10 and 9 in the vapor-mains 5 and 7 respectively. Nowturn steam into efiect C at N and open he valve in the brine feed f lineto effect and regulate to maintain the desired brine level in 0. Openthe cocks 30 and. 46 part way by turning their levers toward efl'ect A'and regulate the 'fejed-from O toB by one of the cocks tomaintain thedesired level of brine in eflect I B, and open thefcocks 32 and 39 partway by turning their levers toward effect A, and by one: or the othercocks regulate the flow or feed of brinelfrom effect B into efi'ect A tomaintain the desired brine level in A. The

triple effect is now operating with C the hottest efiect'and A thecoolest eifect. Brine is circulating from the bottom of effect C throughthe settler S and back into. C

' through the top, depositingin the settler the 'which it is taken awayby the bucket elevator E. The salt crystals are moved from the settlerS, now serving for efl'ect G, into ctl'ect B by the brine circulatingfrom the bottom of e'fiect B through the lower part of settler S as ledby the pipes 29, 31 and 43 and cocks 30 and 46, and the salt crystalsare moved from the settler S, now serving for effect B, into effect A,by the brine circulating from the bottom of effect A' through the pipes29, 33 and 41, and the cooks 32 and 39. The levers of alt the cocks ofthe appa- I'atus are now inclined towardthe efiect A (now the coolest),as indicated by the short dotted line at each cock, the brine and s11 tare. moving from the effect C toward t effect A, and the vapors aredoing the same,

namely as per the double barbed arrows on the vapor mains 6 and 4.Reversing back to \vorkwith A the hottest etfecjindc the,

coolest effect is done in a manner similar to V the reversing justdescribed. Steam is changed from eflect G to effect A, the water ischanged from condenser 13 to condenser 15 and the cocks are manipulatedas described only the levers are moved in the opposite direction whichbrings them back into the positions shown in Fig. 1. It is to beobserved that each settler serves one or the other of the adjacenteffects depending upon whether A, is the hottest effect or the-coolesteffect.

Elfects A and C are considered adjacent to the open settler S In theforegoing descriptions, the feed of brine is into thehottest efiect, anddown from body to efl'ect to the coolest through the intermediatesettlers. The brine, however, may be made to flow in the oppositedirection, viz., into the coolest effect and from effect to effect tothe hottest effect; for example, if when A is the hottest etfect thefeed of fresh brine be taken into the coolest effect 0, as regulated bythe valve in the feed pipe 7', the brine may be caused'to flow into theeffect B from C by regulating the cocks 30 and 46 so that the flow intothe settler S from C, through the pipes 29 and 31 shall be in excess ofthe flow from the settler back into C by the pipe 44; this excess orfeed finds its way into the effect B from the'settler with thecirculating liquor through the pipes 36 and'39 and the cock 37, and itsquantity may be regulated to maintain a desired level of brine in eiiectB by one of the cocks 30 and 46. In a similar Way brine may be made tofeed from effect B into A to maintain the desired level in A bymanipulating the cocks 32 and 39. The circulating pumps exert suliicientpressure on the brine to move it forward in this maning pressures whichcorrespond to the increasing temperatures.

- The brine 1n the'efiects may be carried at different levels with theeffect of obtaining different size salt crystals. If the brine level nerfrom effect to effect against the increasbe carried below the lower rowof tubes, the

crystals obtained will be the finest, for the brine is always in a highstate of agitation due to its falling from tube 'to tube during all ofits passage over the evaporating tubes suffering evaporation. If thebrine level be jcarriedfabove the upper row of tubes, the brine, itevident, will be in a comparatively low degree of agitation during theevaporation'a'nd the crystals formed will be larger. "With" the brinecarried at intermediate levels,'the"average of the grains produced willbe of an intermediate size.

Itis evident that there' may be a greater number of effects in t-heseries'and a correspondingly greater numberof settlers and have theconnections between the parts and the -operation similar to that hereindeocate-z "scribed for a series of three effects, and also of myapplication #575,371, filed August iird, 1910, and still meet the termsof my invention in a number of particulars.

Methods of working which are involved in 3 the preceding description, as.for example the varying of the size of the salt crystals by varying thelevels at which the brine is carried in the eftectswfll' be covered inother applications for Letters Patent of the United States. i

I claim as of my invention-- l. The combination with the effects ofmultiple effect evaporator oi two-or more effects arranged with respectto its steam and vapor connections so that it may be operated witheither end effect the hottest effect, the combination with the effectsof a settler for each pair of adjacent effects with pipe connectionsbetween the settler and each of the effects of the pair to connect itwith either effect of the pair desired in a circulation relation andmeans for circulat ing the brine, from the effect through the settlerwith which it is connected and back into the body again substantially asdescribed. a a

2. In the combination with the effects of a vapor reversing multipleeffect with a settler for eachpair of adjacent jeflects, pipeconnections from each effect to the portion of the settler inwhieh theseparated crystals deposit and back to the eflect and means forcirculating the brine from the effect through the settler and back to:the effect to move the deposited crystals from the settler into theeffect substantially as described.

3. A multiple efi'ect evaporator for the manufacture of salt from brinebyevaporation, in which salt crystals are formed in the brine in two ormore of the effectaa device for separating salt crystals from brine,meansfor causing a flow of brine through a suitable conduit into thesaid device sufiiciently rapid to move salt crystals through the conduitinto the said device, and means for delivering the salt crystals formedin the two or 'more effects into the said conduit and into the brinefioWin through the conduit to the said device or separating saltcrystals from brine.

4. A multiple effect evaporator for the manufacture of salt from brineby evapora-,

tion, in which still; crystals are formed in the brine in two or more ofthe effects, a device for separating" salt crystals-- from brine, meansfor causing a flow of brine through a suitable conduit intoithe saiddevice sufiiciently rapid to move salt crystals through the conduit intothe said device andmeans for delivering the salt crystals formed in thetwo or more effects into the said conduit andinto the brine flowingthrough the conduit to the said device for separating salt crystals frombrine and means for delivering back into the multiple effect the brineafter'the salt crystals have been separated from it.

A vapor reversingmultiple effect'evapo rator for the manufacture of saltfrom brine by evaporation in which the. steam and vapor connections aresuch as to permit of either endeflect serving as the hottest-eflect-,and the other end efl'e'ct as the coolest eflect,

' means for taking away salt formed in either end effect in a current ofbrine to a device for separating salt from brine, and means fordelivering saltformed in other efi'ects of the multiple'e-ffectinto thesame current of brine.

6. In a vapor reversing multiple effect for the manufacture of salt frombrine by evaporation, means for reversing the direction of the vaporsand heat through the effects as a series, and means for reversing thedirection of the movement of the salt formed in the several efl'ecfsalong the series of effects to correspond with the said direction of thevapors and heat.

7. A multiple effect evaporator for making salt from brines byevaporation, in which salt crystals arc tormed in-the brine in two ormore of the effects; means for 001- looting the salt crystals formed inthese eflects into one of. the effects of the multiple cficct, a devicefor separating salt crystals from brine, and means for delivering saltcrystals suspended in a current of brine from the said one efiect intothe said device for separating salt crystals from brine.

8. A multiple effect evaporator for mak IOU ing salt from brines byevaporation, in

which salt crystals-are formed in the brine in two or more of theeffects; means forcollooting the salt crystals formed inothese effectsinto: one of the effects of the multiple effect, a device for separatingsalt crystals from brine, and means for delivering salt crystalssuspended in acurrent of brine from the said one effect into the saiddevice for separating salt crystals from brine, and.

means for delivering the brine separated from the salt'back into themultiple 'efi'eot.

9. A multiple eflect evaporator for the manufacture of salt from brinesby evaporation, in which the salt crystalsare formed in two or more ofthe efiectsymeans'for collecting saltformed in the several effects intoone efi'ect and means for taking the salt away from the said o'neefi'ect and thereby away from the multiple effect.

10. A multiple effect evaporator for the manufacture of salt by theevaporation of brine in which salt forms in the-several efi'ects; meansfor delivering salt from each ofthe hotter effects into the coolestefiect, and means for taking the salt away from the coolest eflect, andthereby from the mul- 5 ti-ple effect. 7 I 11. A series of evaporators'for the manufacture of salt from brine by evaporation, in which seriessalt is formed in each of the -evaporators, a collecting evaporator forthe It salt from all the evaporators of'the series;

means for delivering the salt formed in each evaporator through all theevaporators in succession between it and the collecting evaporator andthen into the collecting 15 evaporator and means for removing the saltfrom the collecting evaporator and thereby from the series ofevaporators.

'12. An evaporator for making salt from ubrines by evaporation, having asalt settling 29 space into which the salt settles away from theevaporating brine, a brine holding tank, means tor maintalning anadequate volume of v brine in the tank, and means for deiivering thesalt from the salt settling space of the evaporator suspenderi in acurrent of brine into the saicl brine tank ancl permit ting the salt tosettle through the M1119 in back into the evaporator from the tank.

13. An evaporator for making salt, from brines by evaporation, having asalt settling space into which the salt settles away from theevaporating brine a brine holding tank,

] W itnesses: MARY T. Miacmenn, JOHN J. liar/res.

the tank, and means for delivering brine means for main aining anadequate oluine,

